Ducts are extensively utilized in heating and ventilating systems to distribute heated or cooled air throughout a building structure. These ducts are commonly formed from differing gauges of sheet metal, or the like, in portions of predetermined lengths which are then connected to one another to form a continuous duct system for distributing air.
With known apparatus for manufacturing ducts for use in HVAC systems and the like, a series of bends are made in a metal web to form a duct blank. A seam is then pre-formed at an open corner of the duct blank by aligning and then bending free edges of the partially formed duct. Typically, the duct blank is then removed from the apparatus along the line of the seam, and the seam is closed manually to form a complete duct blank. Final closure of the pre-formed seam is accomplished manually to accommodate varying duct sizes and to accommodate the need for bracing of the duct blank during seam closure. However, during removal of the duct blank from the apparatus, the free edges in the pre-formed seam tend to separate, requiring the seam to be manually reformed prior to final closure. Thus, making ducts according to the known apparatus is inefficient at least because the free edges must be manually aligned, bent, and closed.
With the foregoing problems and concerns in mind, it is the general object of the present invention to provide an integrated apparatus for in-line manufacture of ducts.